List of unsolved problems

This is a list of lists of unsolved problems in various subjects:

• Unsolved problems in mathematics
• Unsolved problems in physics
• Unsolved problems in chemistry
• Unsolved problems in biology
• Unsolved problems in economics
• Unsolved problems in governance
• Unsolved problems in cognitive science
• Unsolved problems in neuroscience
• Unsolved problems in computer science
• Unsolved problems in software engineering